The present invention relates to a novel long-acting injectable veterinary composition comprising a spirocyclic isoxazoline compound and at least one biopolymer for treating an animal with a parasitic infestation, particularly an ectoparasitic infestation. The biopolymeric composition can be prepared as a solution or suspension for subcutaneous injection. The spirocyclic isoxazolines of the instant invention were originally disclosed in WO2012/120399. The present invention provides an improved long-acting injectable composition for the treatment of a parasitic infestation in an animal. The injectable biopolymeric composition has unique properties including: versatile degradation kinetics, duration of efficacy, and established safety.
Polymeric microparticles have been used for drug delivery for numerous pharmaceutical uses. For example, U.S. Pat. No. 6,726,918 describes a biodegradable implant containing dexamethasone for treating inflammatory ocular conditions; and U.S Patent Application No., 2006-0173060 describes biopolymer microparticles containing an alpha-2-adrenergic receptor agonist for treating glaucoma. Other conditions treated with biopolymer compositions include doxycycline hyclate for periodontal disease, and leuprolide acetate for prostate cancer and endometriosis. Biopolymers have not been described for use in preparing long-acting injectable antiparasitic compositions.
Compositions currently available for parasitic treatment generally include topical, oral, and injectable compositions for animals and do not always demonstrate good activity, good speed of action, or a long duration of action. Most treatments contain hazardous chemicals that can have serious consequences, including lethality from accidental ingestion. Persons applying these agents are generally advised to limit their exposure. Pet collars and tags have been utilized to overcome some problems, but these are susceptible to chewing, ingestion, and subsequent toxicological affects to the animal. Thus, current treatments achieve varying degrees of success which depend partly on toxicity, method of administration, and efficacy. Currently, some agents are actually becoming ineffective due to parasitic resistance. Hence, there is a need for a stable, long-acting, easily administered, and effective long-acting injectable antiparasitic composition.
The veterinary biopolymeric composition of the present invention provides long-acting efficacy in animals against ectoparasites over other known injectable parasiticides.